Letter feed and separator unit



Jam 3 1945- ABURCKHARDT ETAL 2,368,5

LETTER FEED AND S EPARATOR UNIT Filed March 11, 1942 2 Sheets-Sheet 1 ATTORNEY Jan. 30, 1945. A. BURCK'HARD'I; arm. ,5

LETTER, FEED AND S'EPARATOR UNIT Filed MarGh I1, 1942 2 Sheets-Sheet 2 y I 1 W nun y 3 E v I 2 w ATTORNEY Patented Jan. 30,1945

, AlfredBurckhardt, Stamford, and Edward A. Sammis, Springdale, Conn.,' assignors to Pit.- ney-Bowes Postage Meter 00., Stamford, Conn., a corporation of Delaware Application March 11, 1942, Serial No. 434,258

4 Claims.

This invention relates to a combined letter stripping and Separator unit which isparticularly adapted for use in a metered mailing machine or the like, where letters are stripped from the bottom of a stack of superimposed letters, one, at a time, and are then fed to'a printing station.

In devices of this character now in common use, stripping means is adapted to intermittently engage the lower surface of the lowermost letter of a stack of letters and, through frictional'engagement therewith, move said letter from the stack to a letter feeding position. To restrict the feeding to a single letter at a time, restriction means is provided in the form of frictional surfaced members -which normally lie in the path of the letters immediately above the lowermost letter to obstruct movement thereof.

It is the principal objectof this invention to provide in a letter stripping and separator unit, means wherein thefeedin elements possess charwithout departing from the spirit of the invention. I: e v

A preferred embodiment of the invention is i1- .lustrated in the accompanyingdrawings, wherein:

Fig. lis aside elevational View with parts broken away, showing a letter feeding and separator unit, and including a letter stripping element arranged in an operative position about to engage and strip the lowermost letter, from a stack of letters;

Fig. 2 isan elevational viewwith parts in sec- I tion and taken. along the line 2-2 of Fig. .1;

acteristics which are inducive, to improved letter feeding I and wherein the separator elements possess characteristics which are inducive to improved separation.

With regard to the feeding elements of the unit, it is an object to provide in one element which cooperates with the stripping element, means which possesses sufficient mass and tension to cooperate most advantageously with the. letter stripping means.

With regard to the separator elements, it is the object to provide mean having a high frictional coefiicient and supported under a very light tension, the frictional force being ample to overcome the friction resulting from the drag Of the lowermost letter across the lower surface of an adjacent letter without causing any appreciable resistance to thenormal feeding force. I

It is a further object 'to provide two independently movable separator element spaced apart, and to connect same in such manner that the tensionon each is equalized.

It is a further object to provide anti-friction rollersopposite the separator elements to thereby decrease friction between the lower surface of the stripped letter and the supporting surface at the point of separation.

With the above and other objects in view, which will appear as the description proceeds, the invention resides in the combination andarrangement of parts and in the details'of construction hereinafter described and claimed, it being under- 7 stood that various changes in the precise embodimentof the invention herein disclosed may be made within the scope of what i claimed Fig. 3 is a fragmentary view similar to Fig, 2, but showing the affect which a letter of uneven proportions has upon the separator elements; and

Fig. 4 is asectional view taken along the line 4-4 of Fig. 2.

Referring to Fig. 1, wherein a portion of the letter stripping and feeding devices of a metered mailing machine are shown, the mechanism-il- .lustrated includes a letter feed hopper lflhaving a stack of letter I I shown therein, a letter feed plate [2, a stripper element 13, and driven letter feed means l4. I'he letter feed hopper Illincludes anend wall I 5 which has its lower surface spaced above the feed plate l2, to provide space through which the letters .I I pass during strip- Dl On the outside of the wall l5, thefeed and separator unit i mounted, whichunit includesa feed shoe [6 and separatorrollers ll-lla.

The feed shoe preferably comprises a block of solid metal which is suspendedfrom arms l8 and [9, said arms having their forward ends connected with the shoe at 2| and 22 respectively, and their rearward ends connected with rods .25" and 26.

' Said rods 25 and 26 are supported insuitable lugs 2324 projecting from the wall l5. By reason of this means of mounting, the shoe will be suspendedfrom the ends of the arms I8 and "hand owingto the mass or weight of said shoe it is nor mally urged toward the feed plate l2. By means I of'an adjustment screw 21, however, ,which passes through'the upper end :of the shoe and which has v its inner end in engagement with a yoke portion 20 of thearm I9, the said shoe is adapted to be adjustedslightly above the feed plate 12. This I adjustment is usually made to. accommodate the thinnest piece of mail-matter which passes therebeneath, as for instance a postcard. V

' In addition to the weight of the shoe' 16, tension is also applied by means of a spring 28 which is wrapped around a sheavewheel 29 and has one end anchored to a pin 3| and the other end anchored to a pin 32. Saidsheave wheel stripper element may be of any common form and in the present. instancecomprises a pulley 33 supported on a power driven shaft 34. Attached to said pulley 33 is a shoe 35 having a preferabl frictional surfaced portion, as indicated at 36. A frictional belt 31 is also provided on the pulley 33.

Said pulley 33 and shoe 35. are arranged beneath and at either side of the feed shoe. [6 as, best shown in Figs. 2 and 3,' andowing to the. surface contour of each, are adapted to engage,

the lower surface of the lowermost letter in the stack and. lift same slightly When'the letter is impinged between the stripper means l31and the feed shoe 16. The frictional engagement of the strippermeans -eifects the initial pickup and feed of the lowermost letter which is immediately assisted by the counter pressure applied by the feed shoe-16. According to-this method of feeding-the weight of 'the shoelii produces a strong counter force when the. letter is moved by the frictional engagement: of the stripper element therewith, to thereby effectively grip the letter. Further, "the lower surface of the shoe I6 is polished smooth 'to provide a minimum of friction. Tofurther reduce the frictional contact of the letter surface during initial feeding or stripping, anti-friction rollers 33-38 are positioned directlybeneath the letter surface and at either sideof the pulley 33' and shoe 35;

Feeding isefiected, therefore, during each rotation of the pulle I 33 and shoe-35, when the frictional surfacest ereofengage with the lower surface of the lowermost letter and move said letter forward 'a sufficientdistance to permit same-to be engaged by the letter feed-belt of the letter'feed-means ill for further conveyance.

During the feeding of a letter, means is provided toprevent these letters immediately above the o'n e which is fed from advancing. Said means i's'knowrr as separation and in the construction hereprovided, comprises the separator rollers l'llla. which are provided with a pref-- the rods 25 -26 by links 44 and 45 respectively, By this arrangement of supporting structure, each roller 11 and Ila; is independently movable.

The supporting brackets Al and Ha for said rollers and we are flexibly connected, however; by'means of a bridging rod or whifile tree 46, which has the. opposing ends thereof. freely positionedfin suitable openings within the bracketsl'l and Ma respectively.

Tension is also provided to urge the. rollers ll-lla in a downward direction, and is so. arranged that an increase in tension on one roller, resulting from the rise of said roller to a position higher than the other, will cause a similar increase in tension on the opposite roller. Such compensating oftension is provided by directing In a like. mannerthe bracket 41a is connected with the force of the tension to a position midway between the ends of the bridging rod 46. This is effected by pivotally mounting an arm 41 on rod 25 in such manner that the free end thereof 48 will engage the center of the bridging rod 46, a knife edge 49 being provided at the free end 48, which is adapted to ,fit within a groove 5| in the bridging" rod 46 for this specific. purpose. A spring 52 is then stretched between the arm 41, and an anchor pin 53, to provide tension for each of the separator rollers I1 and Ha.

It. willbe seen. that so long as the rollers l1 and. Ila are on. the same plane the tension upon eachroller will be substantially the same. It is .--further apparent that when a letter passes beneath the separator rollers which is higher along one side than the other such as indicated in Fig. 3, the lift of the roller on the higher side will effect an increased tension thereon, but owing to the fact that the tension is applied at the center of the. bridging member, or rod 46, the same increase of tension. will beapplied to the opposite. roller- Bythis novel means of equally distributing. the tension, letters move along a straightpath andiskewing is avoided.

Bymeans. of. the above named arrangement for the mounting of'both the feedshoe and the separator rollersasa unit, a careful balance has been provided, whereby feeding of the letter is enhanced; first, as a result of the mass or weight of the feed shoe plus the tension provided therefor, which acts as a counter force and cooperates most effectively with the stripper element l3; and secondly, as a result of the light tensioned flexible mounting for the: separator rollers, including their high frictional coefficient which repel the advancement of thoseletters directly above. the. one which is being fed, yet with a minimum of counter frictional effect upon the letter which is being fed.

From Fig. I it will be noted that the inner contour of thelower surface of the feed shoe [6 is.also shaped to provide for pre-separation of the letters as they approach a stripping position.

Having described the invention what is claimedis:

1. In a letter stripping and separator unit, stripper means engageable with one surface of a letter to effect'stripping thereof from the bottom of a stack of superimposed letters, an anti-friction feed shoe comprising mass and engageable with the opposite surface of the letter to effect an opposing force and thereby increase the bite betweensaid stripper means and feed shoe, and a plurality of spaced and independently movable separator members having a high frictional coeihicient and positioned in the path of the letters.

2. In a letter stripping and separator unit, stripper means engageable with one surface of a letter to .eifect stripping thereof from the bottom of a stack of superimposed letters, an anti-friction feed shoe comprising mass andengageable with the opposite surface'of the letter to effect an opposing force and thereby-increase the, bite between said stripper means and; feed shoe, a plurality of spaced and independently movable separator members having; a high frictional coefiicient'and positioned in the path of the letters, and anti-friction rollers positioned opposite the separator members.

3. In a letter stripping and separator unit, stripper means engageable, with one surface of a I letter to effect stripping thereof from thebottom of a stack'of horizontally disposed superimposed letters, a feed'shoe comprising mass and'engageletters, a feed shoe comprising mass and engageable with the opposite surface of the letter to effect a relatively heavy counter force and thereby assist said stripper means during letter stripping, two spaced and independently movable separator members having a high frictional coefficient and positioned in the path of the letters at either side of the feed shoe, and tension meansconnected with the separator members to effect a. relatively 10 light drag upon a letter during stripping.

ALFRED BURCKHARDT. EDWARD A. SAMMIS. 

